A locking device of the kind mentioned above is known from document DE 10 2010 044 702 A1 and serves for fixing a rigid roof element, which can be a front bow of a folding top or a rigid roof segment of a retractable hard top (RHT), to the front cowl of the vehicle in question. The locking device comprises a locking support, which serves as a casing and which can be connected to the rigid roof element. Furthermore, the locking device comprises a locking hook, which is pivotably mounted to a crosshead movable in the locking support. The locking hook can be displaced between a raised locked position and a lowered release position by moving the crosshead in the locking support. In the locked position, a hook section of the locking hook is engaged with a corresponding locking element, which is formed on the front cowl. For driving, the crosshead is connected to a driving disk via a linkage arrangement, said driving disk being able to be driven in a rotational manner by means of a driving motor. The driving disk comprises a switching gate at its upper side, said switching gate interacting with two end-position sensors, one of which being allocated to the release position of the locking hook while the other is allocated to the locked position of the locking hook. Intermediary positions of the locking hook cannot be detected by the sensors, which are realized as microswitches. In fact, only the end positions of the locking hook can be prompted.
Alternatively, it is known that the position of a locking hook can be detected by means of a Hall sensor, which interacts with a driving wheel of a driving motor and counts the rotations of the driving motor for detecting the position of the locking hook. In the event of a power outage, however, the current position of the locking hook would be lost in this embodiment.
When a top is displaced from the closed position to the storage position, it is necessary for the locking hook of the locking device to be retracted in order to avoid collision with a covering of the top storage compartment. If the displacing movement of the top is stopped in an intermediary position while the locking device or rather the locking hook of the locking device is not in an end position and the top is then moved in the other displacing direction, it has been necessary thus far to stop the top for a short moment until the locking hook has taken up the desired end position again. Otherwise, it would not be ensured that the locking hook has taken up its required end position, i.e. its release position or locked position, respectively, when reaching one of the top end positions.